[Harp-L] Re: harmonica microphone cables - impedance matching

[BluzeHarp@xxxxxxx]

How much of a 'sin' is it to plug in a Shure blues blaster mic to a Music  
Man tube amp without using an impedance matching transformer (I realize it  
wouldn't really be considered a sin as much as it could possibly be 
considered  poor practice). :-) 


John, there is no such thing as a "Shure blues blaster".  The Blues  
Blaster is essentially the same crystal element mic as a JT-30,  it is made by 
Astatic and distributed through  Hohner.  This is a high impedance mic and 
should be plugged  directly into your guitar/harp amp.  There is no need  to use 
an inline matching transformer with a Blues Blaster into your Music  Man 
amp, doing so won't damage your gear, but it will  definitely change the 
output in an undesirable manner.  For the  purposes of this thread, a matching 
transformer is typically  used when using a LOW impedance mic such as a  Shure 
SM57 to a guitar type amplifier.  
 
If you are experiencing low output with a Blues  Blaster it likely means 
that the crystal element is bad.  If you have  no output at all it could be a 
bad element, internal wiring problems, a bad  volume pot, a bad cable, or 
the wrong cable... the Blues Blaster comes  from the factory with a 
'non-standard' Pin 3 hot XLR connector and will not  work with a standard Pin 2 hot 
XLR mic cable.  There are  additional details about this plus a lot of related 
info in my  free 'Harp Mic Buyers Guide'... which can be requested any time 
by  visiting my Harmonica Planet website.  You can also subscribe there to  
the monthly Colorado Blues Jam Post.
 
Regards,
 
Christopher Richards
Twin Tone Harmonica Microphones    harmonicaplanet.com
Co Producer - Greeley Blues Jam    greeleybluesjam.com
Stage Manager - 2012 SPAH Convention    spah.org
Author/Publisher - The Colorado Blues Jam Post